Micro Metal Gear DC Motor (30 RPM) 6V .

From the shop's description

N20-6V-30 Rpm Micro Metal Gear Motor is a small volume, big torsion, all metal gear. dimensions : 12mm x26mm x 36mm Features Gear ratio: 30:1 rpm @ 6V: 30 Rpm Stall current @ 6V: 420mA Stall torque @ 6V: 800 g.cm Weight: 10g Micro Metal Motor Datasheet